Power rating

Definition

The stated power of an appliance under its intended operating conditions.

Used by AQA, Edexcel and OCR

Specification 4.2.4.2 · Paper 1

The power at which an appliance is designed to operate normally; it states how many joules the appliance transfers each second.
Revise: Energy transfers in everyday appliances

Specification 10.42 · Paper 2

The rate at which an appliance transfers energy when it is operating normally, usually stated in watts or kilowatts.

1
A higher power rating means more energy transferred each second, not necessarily more energy transferred overall; the operating time also matters.
2
When comparing two power ratings, state that the higher-power appliance transfers more energy each second. Only claim that it transfers more energy overall if the operating times are the same or have been considered.
3
A higher power rating means more energy is transferred each second, not necessarily more energy overall. Total energy also depends on how long the appliance operates.

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The power rating states how rapidly an appliance transfers energy when working normally.

Specification P7.2c · Paper 2 (Foundation), Paper 4 (Higher)

The manufacturer's stated power of an appliance under its intended operating conditions.
The value printed on an appliance is its power rating. A larger rating means a greater rate of energy transfer. It does not mean that energy is destroyed or “used up”: energy is transferred between stores and is conserved overall.
Revise: Power ratings

Paper 1, Paper 2

An appliance’s power rating therefore tells you how quickly it transfers energy when operating at that rating. It does not tell you the total energy transferred unless you also know how long the appliance operates.
Revise: Electrical Energy and Power Usage
The stated rate at which a device transfers energy when operating under its specified conditions.
Revise: Energy and Power in Electric Circuits